Excavating machines for digging in rock type formations usually employ a combination digging tooth and holder comprised of a rock type bit having a shank which is rotatably received within a bore formed within a block. The block is a body of metal that is welded onto whatever mechanism the excavating machine may employ for manipulating the digging teeth. For example, in a wheel type digging machine, the blocks will be welded to the outer circumferentially extending surface of the digging wheel so that the digging teeth engage and remove the geological formation being traversed by the machine.
During the excavation of geological material from the earth, it is not uncommon to observe the formation change from a rock type formation to dirt, sand, clay, or other soft formations that do not require a rock type bit. In fact, a rock type bit does not perform satisfactorily in these loose, dirt type formations and it is therefore necessary to either change the digging teeth to a wider, more efficient dirt type tooth, or change to a machine that includes the appropriate digging teeth.
It would therefore be advantageous to be able to change the digging teeth associated with a digging machine from a rock type bit to a dirt type digging tooth, and vice versa, depending upon the formation encountered by the digging machine. To be able to quickly change from a rotatable rock type tooth to a wide, non-rotatable, dirt type tooth requires that means be provided by which the dirt type tooth is rendered non-rotatable, and this non-rotatable tooth is the subject of this invention.